To abandon or not?

It used to be a source of pride that I would not abandon a book no matter how mediocre. That has been tested recently with several titles that I've been picking at for months. Complicating things are that some are review copies. I'm thinking I might do a roundup post where I at least mention the book and give one or two thoughts on why I can't seem to finish it. If the review outfits want to black list me that's their business. Any thoughts?